Vacuum bags in 20 mil vinyle. Generally speaking, vinyl is fine for flat or modestly curved work and for infrequent use. Vinyl is economical. Economical cost Three track "quick zip" bag closure system Electrically welded seams Completely transparent 280lb tear strength resistance 135 degrees F temperature resistance Shipping / Billing Information This product ships direct from the manufacturer: Your order will ship in approximately 5 business days. This product is considered special order. Your account will be charged when you place your order. Express or overnight shipping is not available for this product. Ships by Ground to the 48 contiguous states. Cannot ship to Alaska, Hawaii, PO Boxes, APOs, US Territories, Canada or other foreign countries. Return Information If you have a return issue, contact Woodcraft Supply customer service @ 1-800-535-4482 for return details. After 30 days, you will be charged a 25% restock fee. Customer pays return freight. When returning product, please include the invoice number or customer number and refer to the back of the invoice for shipping instructions. If purchased at a Woodcraft Store, please return the item directly to the store where your purchase was made. Warranty Information One year replacement for defective product. Please contact Vac-U-Clamp with warranty issues @ 888-342-8262.